Method and apparatus for loading flash lamps



Dec. 11, 1956 P. A. DELL ETAL 2,

METHOD AND APPARATUS FOR LOADING FLASH LAMPS Filed June 7, 1954 3Sheets-Sheet l /-A /fiz A i. 58 n 59 JCTJ 53 29V 1 55 55 am/kg l 57 l ilnven tors: A PauL A.D8LL, James lLazna, 4 7 47 y I ,1 I E? A Then A'tovnes.

Dec. 11, 1956 DELL ETAL 2,773,520

METHOD AND APPARATUS Fox-7* LOADING FLASH LAMPS 5 Sheets-Sheet 2 FiledJune '7, 1954 lnven torsf Paul, A.D8LL, James J.La2na, b5 6% TheirAtbo1-ne9 Dec. 11, 1956 P. A. DELL ETAL 2,773,520

METHOD AND APPARATUS FOR LOADING FLASH LAMPS Filed June 7, 1954 5Sheets-Sheet I:

F cg 7., 5/ 1 28. 5/

L/ne

fnven tors:

Paul, A.DeLL, James d.Lazna, g m f Their A t orneg.

METHOD AND APPARATUS FOR FLASH LAMPS Paul A. Dell, Highland Heights, andJames J. La zna, Cleveland Heights, Ohio, assignors to General ElectricCompany, a corporation of New York Application June 7, 1954, Serial No.434,918

17 Claims. (Cl. 141--5 LOADING Our invention relates, in general, to themanufacture of flash lamps of the type employing, as the light-producingelement thereof, a quantity of readily combustible filamentary materialin the form of a multiplicity of relatively short lengths of fine wire,or finely cut strands of metal foil such as that commonly referred to asshredded foil. More particularly, our invention relates to a method andapparatus for introducing such type filamentary combustible materialinto, and distributing it within, the bulb of the flash lamp.

The introduction of such type filamentary combustible material into andits distribution within the lamp bulb is usually effected by a pneumaticprocess wherein the material 'is transported by a stream of air flowingthrough a feed tube inserted into and extending through the neck of thebulb into the interior thereof, the filamentary material being carriedthrough the feed tube and deposited in the bulbby the air stream whichthen passes out of the bulb through the neck thereof, through the spacebetween the inserted feed tube and the surrounding bulb neck.

While such a pneumatic loading arrangement can be successfully employedwhere the neck opening of the bulb is of a diameter at least as large asthose present in flash lamp bulbs of the type in general use at present,it has been found impossible to adapt such existing loading arrangementsto the loading of bulbswhose neck openings are of extremely, small sizesuch as for example, the inch neck opening of a miniature flash lamprecently introduced on the market. In such cases, because of theunavoidable limitation on the size of the air outlet pas-,

sageway between the inserted feed nozzle and the. surrounding bulb neck,the exit velocity of the foil-transporting air stream out of the bulb isso high as to promptly carry or sweep the introduced filamentarymaterial right out of the bulb.

It is an object of our invention, therefore, to provide a method andapparatus for automatically introducing filamentary combustible materialinto, and uniformly distributing it within, flash lamp bulbs havingextremely small size neck openings.

In" accordance with one aspect of the invention, the

to fluff out the filamentary material introduced into the bulb andredistribute it uniformly throughout the interior space thereof.According to a further aspect of the invention, the loading orfillingnhead in which the bulb is mounted for the introduction of thefilamentary combustia ble material thereinto by the air stream isprovided with supplementary air jetmeans arranged toeither bleed airfrom the surroundingatmosphere, or tobeconnected-to a lowpressurecompressed air source, tothereby directa low velocity stream ofair into the bulb at an angle to the axis thereof and concurrently withthe introduction of the filamentary material into the bulb, for thepurpose of flufting out the filamentary material in the bulb and redis-.

tributing it uniformly throughout the interior space thereof.

Further objects and advantages of our invention will appear from thefollowing detailed description of species thereof and from theaccompanying drawing.

In the drawing,

Fig. 1 is a vertical section through amidportion of apparatus comprisingour invention and showing a miniature flash lamp bulb in loadingposition therein;

Fig. 2 is an enlarged sectional view of the filling head of theapparatus, showing, a bulb in loading thereon;

Fig. 3 is an elevation of a completed miniature type flash lamp showingthe manner in which the filamentary position material is positionedwithin the bulb by the method and Fig. 7 is a sectional view of amodified form of filling head according to the invention;

Fig. 8 is a sectional view of another modified form of filling headaccording to the invention; and a Fig. 9 is a diagram of the electricalcircuit for controlling the operation of the solenoid'valveswhichregulate the supply of compressed air to the supplementary air, jetmeans of, and the supply of vacuum to, the modified form of fillingheadshown in Fig. 8. In the drawing, the apparatus there shown and theoperation of all the moving parts thereof is the same as that describedand claimedin U. S. Patent 2,347,046, Geiger et. al., dated April 18,194.4, except for the structure andloading. action of the loading orfilling heads 1 and 1a which. are materially different from the loadinghead shown in the said patent. A detailed description of the entireapparatus and its operation is unnecessary 'to a full understandingofthe present invention but may be had, 1 if desired, by reference tothe above-mentioned Geiger;

et, al. patent.

In general, however, the apparatus comprises a cutting mechanism 2 forslicing extremely fine ribbons or shreds from an advancing sheet 3 ofmetal foil such as full hard aluminum foil having a thickness of from.0005 to .001 inchand a suitable uniform width which may range, forexample, from 4 to 8 inches or so. The aluminum sheet 3.is supplied froma roll thereof. (not shown) rotatably mounted on the apparatus, and itis advanced at auniformrate by cooperating feed rolls 4 and 5, betweenwhich the sheet 3 passes, to the cutting means of the apparatus whichcomprises a bed knife 6 and a cooperating" rotatable cutter 7. The speedof advance movement of I the foil sheet 3 by the feed rolls 4, 5 and therotational speed of the rotary cutter 7 are so proportioned as tocutstrips, or ribbons from the sheet 3 of a width of. the order of .0005to .001 of an inch. the apparatus, the cutting of the foil sheet!) bythe knives 6, 7 is interrupted for a short time at regular intervals,after the required number of strips constituting the desired charge fora, single lamp have been cut, by a stoppage of the rotational movementof the feed rolls 4, 5

which thus interrupts the advance of the foil sheet 3 to.

e tter 6, 7.

2,773,520 Patented Dec. 1 1,1956

In the operation of The bed knife 6 is mounted on a bed 8 carried by theframe 9 of the cutting apparatus 2, while the rotary cutter 7. isjourna-lledat opposite ends in extended portions 19 of the frame 9 andis driven from a pulley 11 through the clutch 12 engaging one of saidends. The pulley 11, in turn, is driven by a belt 13 connected to theoutput shaft of an electric motor and speed reducer unit (not shown),and it drives the lower feed roll 5, which is rubber faced, through aspeed reducer 14, the intermeshing gears 15, 16, 17, 18 and 19 of a geartrain 20, and the shaft 21 of the lower feed roll 5. The pulley 11 anddrive gear 15, which as shown in Fig. 6 is in the form of a multi latedor interrupted gear, are mounted on the input and output shafts 22 and23, respectively, of the speed reducer 14, whereas the gears 16, 17 and18 are mounted on pins indirectly supported by the frame 9. The gear 19is mounted on the shaft 21 of the lower feed roll 5.

As the individual foil strands or strips are cut and drop from thecutter knives 6, 7 they are picked up by or drawn into one or the otherof a pair of suction nozzles 26, 260 at the entrance ends of respectivefeed tubes 27, 27a, the nozzles 26, 26a being located directly beneathand contiguous to the cutting edge of the bed knife 6 near themidportion thereof. The feed tubes 27-, 27a are connected to respectivebulb loading or filling heads 1 and 1a which are identical inconstruction and which are mounted on the table 28 of the machine -andare alternately placed in bulb loading operation. The strips or strandsof filamentary material are drawn through the feed tube 27 or 27a by asuction of air therethrough and are discharged from its delivery end 28or 28a which extends upwardly and in a straight path into the lower endor hollow interior 29 of the respective filling head or enclosure 1 or1a with which the feed tube has an airtight connection. The hollowinteriors 29 of the filling heads or enclosures 1 and 1a are alternatelyconnected to a suitable exhaust means or source of vacuum (not shown),such as an exhaust pump, through respective outlet tubes or pipes 30,30a, traps 31, 31a and 32, 32a, interconnecting pipes 33, 33a, andelectrically controlled solenoid valves 34 and 34a, the operation ofwhich is controlled by a two-way acting (single-pole, double-throw)switch 35 (Figs. 5 and 6) such as that commercially known as aMicroswitch. The switch 35 is mounted on an arm 36 extending from themachine frame 9 and periodically interrupts the vacuum connection to oneor the other of the filling heads 1 or 111 while simultaneouslyconnecting theother filling'head to the vacuum line. For the purposes ofthe invention, the exhaust means employed to produce thevsuction in thefeed tubes 27 and 27a during the operation of the apparatus need only besufficient to provide a vacuum of the order of of an atmosphere or so,corresponding to around 7 to 8 inches of mercury. The operation of thecontrol switch 35 for the solenoid valves 34 and 34a is controlled by acam 37 mounted on the constantly rotating output shaft 23 of the speedreducer 14.

From the delivery end 28 of the feed tubes 27 or 27a the foil shreds orstrands are delivered into the lamp bulb or container 38 to be filled.As shown, the bulb 38 is supported for loading on the top end of thefilling or suction head 1 or 1a, with its open neck end 39 extendingdownwardly into the opening 48 in an annular rubber gasket or bulbseating ring 40 bordering the opening 42 in the upper end of the fillinghead 1 or In, so as to locate the bulb neck in vertical alignment withthe straight delivery end 28 of the feed tube 27 or 27a. The bulb 38seats more or less vacuum-tight against the rubber gasket or bulbseating ring 40 on the upper end of the filling head 1 or 1a. When thusseated against the gasket 40 the bulb 38 closes off the opening 42leading into the interior chamber 29 of the filling head, as a result ofwhich the withdrawal of air from the hollow interior 29 of the fillinghead by the exhaust means acts to create a suction in the feed tube 27or 2711' which then draws the strips or strands of filamentary materialtherethrough and into the filling head.

Where the bulb 38 to be loaded with filamentary material is of a typehaving an extremely small size neck.

opening, such as the 4 inch neck opening of the miniature flash lamprecently introduced on the market, it has been found impossible to usethe form of loading apparatus heretofore commonly used for such purpose,such as disclosed in the aforementioned Geiger et al. patent andprovided with the conventional foil pickup nozzle and loading headconstruction wherein the delivery or inner end 28 ofthe feed tube isinserted into the bulb to be filled when the bulb is mounted in loadingposition in the loading head. In such case, because of the unavoidablelimitation on the size of the air outlet passage way between theinserted feed tube and the surrounding bulb neck, the exit velocity ofthe filamentary materialtransporting air stream out of the bulb is sohigh as to instantly sweep the introduced filamentary material right outof the bulb.

An alternative way of introducing the filamentary material into thebulb, which would avoid the above-mentioned difficultyof sweeping thefilamentary material out of the bulb after having once been introducedthereinto, is to use the loading method and apparatus disclosed andclaimed in co-pending application Serial No. 239,561, R. M. Anderson,filed July 31, 1951, now Patent No. 2,722,355 issued November 1, 1955,and assigned to the assignee of the present invention. In this loadingmethod and apparatus the bulb 38, in place of being supported in aloading position on the filling head 1 such that the delivery end 28 ofthe feed tube 27 actually extends into the hollow interior of the bulbas has been the prior practice heretofore as disclosed in theaforementioned U. S. Patent 2,347,046, is mounted instead in a positionsuch that the open neck end of the bulb is wholly spaced from or above.the upper extremity 41 of the delivery end 28 of the feed tube 27 sothat the latter does not actually extend into the bulb. With such anarrangement, because of the withdrawal of the air from the filling head1 at a region (i. e., at the opening to the vacuum line 30) below orback from the delivery end extremity 41 of the feed tube 27, the aircurrent flowing through the feed tube 27 is, upon emergence therefrom,abruptly diverted laterally away from the delivery end of the feed tube(as shown by the solid line arrows in Fig. 2) and away from the openneck end of the bulb so that it does not actually enter the bulb,thereby creating a virtual dead air space in the bulb. The net result isto cause the filamentary material entrained in the air stream in thefeed tube 27 to be fiung out of the abruptly diverted air stream byreason of its own inertia and projected straight out from the deliveryend 28 of the feed tube into the open neck end 39 of the partiallyevacuated bulb and into the interior thereof. Because the air streamemerging from V the feedtube in this form of loading head arrangementdoes not enter the bulb but instead is diverted sharply away therefrom,there is therefore no possibility of the filamentary material beingswept out of the bulb by such air stream after once having beenintroduced thereinto,

- such as occurs when the conventional type loading method openings oflarger size such as have been customarily employed heretofore in flashlamps, the use of the modified loading method and apparatus of theaforesaid Anderson application Serial No. 239,561 will also operate todistributethe introduced filamentary material more or less uniformlythroughout the interior space of the bulb after its introductionthereinto, such uniform distribution being necessary to the productionof uniformly performing flash lamps and also to the realization of thefullest light-producing potential of the charge of filamentary materialin the bulb. However, in the case of bulbs having very small size neckopenings, such as the 5 inch neck opening of the miniature butt-sealtype flash lamp recently introduced on the market, such a modifiedloading method and apparatus will not dispose the filamentary materialin such a uniformly distributed manner throughout the bulb but insteadwill dispose it therein in what may be termed a spined condition orarrangement wherein it is located or concentrated more or less in theform of a curl or column extending along the axis of the bulb.

In accordance with the invention, we have found that the charge offilamentary material for miniature type flash lamps having extremelysmall size bulb neck openings such as, for example, a X inch neckopening, can be satisfactorily introduced thereinto and distributed inessentially uniform manner throughout the interior space of the bulb byemploying the loading method and apparatus of the aforesaid Andersonapplication Serial No. 239,561 in combination with a supplementary lowvelocity fiufiing air jet directed into the bulb concurrently with theintroduction of the filamentary material thereinto and at an angle atleast of the order of to the bulb axis. For the purposes of theinvention, therefore, the filling head 1 is of the general formdisclosed and claimed in the aforementioned Anderson application SerialNo. 239,561 wherein the delivery end 28 of the feed tube 2-7 terminateswholly within the interior 29 of the filling head 1 so as to space theupper end extremity 41 of the feed tube from the open neck end39 of thebulb 38 seated in loading position on the rubber gasket or bulb seat 40.As shown, the interior wall of the'fillinghead 1 converges upwardly to adiameter, at its upper or open mouth end 42, approximately correspondingto or slightly smaller than the inside diameter of the neck 39 of thebulb 38 to be filled. This converging interior wall 43 of the fillinghead thus provides, in effect, a funnel-like surface for guiding thefilamentary material into the open neck 39 of the bulb 38 and into theinterior of the latter.

The filling head 1 is provided, in accordance with the invention, withsupplementary unitary-finding air jet means which, in the form of theinvention shown in Figs. 1 to 5, comprises a small diameter air tube 44disposed within the interior 29 of the filling head l and having itslower end 45 extending through the wall of the filling head and open tothe atmosphere. At its upper end the air jet tube 44 extends through anda sufllcien-t distance above or beyond the mouthor top opening 42 of thefunnelshapcd passageway 43 in the filling head to locate the upper ornozzle end 45 of theair jet tube 44 within the neck portion 39 of thebulb 38 when the latter is seated in loading position on the blubseating ring or gasket 45 of the filling head. In addition, the upperend portion of the air jet tube 44 is bent or inclined at a slight angleof at least approximately 15 and preferably around 30 in the case of theparticular bulb shown (but in no event greater than 90) to the vertical,and thereforeto the axis of the bulb-38 when seated in loading posit-ionin the filling head 1, to thereby directthe airjetemanab ing from thenozzle end 45 at acorresponding angle into the interior of the bulb, asdenoted by the solid line arrows in Fig. 2. Also, the nozzle end ,45 ofthe air tube 4-4 is preferably flattened to a slight degree ,(e. g, toproduce a nozzle opening having a length of the order of twice the widththereof) in a plane transverse to the plane defined by the bent airtube. A fan-shaped jet or current of air, directed upwardly along oneside of the bulb and having the general path or course denoted by thesolid line arrows in-Fig. 2, is thereby produced in the bulb by the airnozzle 45 whichthen serves to'fiutf out and distribute the filamentarymaterial as it enters the bulb. For best results, the air tube 44 ispreferably bent, at or above the top end 41 of the feed tube, so as toextend at a slight inclination over the top 41 of the feed tube, andtoward and to a point approximately within the projected axis of thefeed tube delivery end 28 where it is then bent back so as to disposethe upper or nozzle end portion of the feed tube at a slight inclinationof at least approximately 15 in the opposite direction, as shown in Fig.2. The gentle flow of air from the air nozzle is produced by thepressure differential which exists between the nozzle end 45 of the airtube 44 and the open lower end 46 thereof when a bulb 38 is in theprocess of being filled with filamentary material. Since the open lowerend 46 of the air tube 44 is constantly open or vented to theatmosphere, the partial vacuum which is created at the nozzle end 45 ofthe air tube 44 by the withdrawal of air from the filling head 1 and thebulb 38 during the bulb filling operation, acts to bleed or draw airfrom the atmosphere into and through the tube 44, thereby producing agentle air flow from the nozzle end 45. For best results, it has beenfound that the cross-sectional area of the passageway in the air tube 44should be within the range of from approximately to the cross-sectionalarea of the bulb neck opening. Thus, for the particular lampillustrated, having a neck opening of approximately 71 diameter, the airtube 44 should have an inside diameter preferably ranging fromapproximately .030" to .045".

The air tube 44 is supported in place within the interior 29 of thefilling head .1 in any suitable manner. At its lower end the air tube 44is supported by reason of the snug airtight fit between the tube and thewall of the opening 47 in the filling head through which the air tubeextends to the outside atmosphere. Preferably, in addition, the air tube44 is also supported at a point near its upper end in order to maintainor hold the nozzle end 45 thereof in proper operative position relativeto the filling head opening 42 and the bulb-receiving aperture 48 in thebulb seating ring 40 against lateral shifting out of the said operativeposition. For such purpose the air tube 44 may be snugly received withina longitudinally extending groove 4d provided in the outer side of thefeed tube 27 at its upper delivery end 28, and firmly held or lockedinplace in such groove by tightly winding a number of turns of bindingwire around the assembled feed tube 27 and air tube 44, as shown at 5%)in Figs. 2 and 4.

While the upper end portion of the air tube 44, because of itsinclination to the vertical, projects across the discharge opening ofthe feed tube 44, and in addition extends through the relatively smallmouth opening 42 of the filling head passageway 43, it nevertheless doesnot interfere with or obstruct the passage of the filamentary materialoutof the open delivery end 41 of the feed tube 44 and into the bulb 38so long as it is of relatively small size in comparison to the size ofthe openings 42 and 48 in the filling head. Thus, in the particular caseillustrated, wherein the mouth opening 42 of the funnelshaped passageway43 is approximately 7 inch in diameter, an air tube 44 made of tubinghaving an outside diameter of around mils will not in any way obstruct.or interfere with the passage of the filamentary material through themouthopening 42 of the filling head and through the bulb neck into thebulb proper. In any case, however, the cross-sectional area of the airtube 44 should not be greater than 20% or so of the cross-sectional areaof the mouth opening 42 of the passageway 43 in the filling head.

In the operation of the loading apparatus shown in Figs. 1, 2 and 4, abulb 38 to :be filled with filamentary material is seated in properloading position on the bulb seat 40 of that filling head 1 or 1a whichis fat that time temporarily disconnected from the vacuum line andtherefore not in operation. Upon subsequent connection of the fillinghead to :the vacuum line through the opening of the solenoid valve 34 or34a by the operation of the control switch 35 in the electricaloperating circuit for the valve, the interior space 29 of the fillinghead and also the interior of the bulb 38 seated thereon is evacuated,creating a suction of air in the feed tube 27 or 2701 which then sucksthe strands of filamentary material into the pickup nozzle 26 or 26a ofthe feed tube as the strands are cut and drop from the cooperatingcutter knives 6 and 7. In addition to creating the suction of air in thefeed tube 27 or 2711, the evacuation of the filling head and the bulb 38seated thereon at the same time acts to bleed or draw air into the openlower end 46 of the fluffing air jet tube 44, thereby producing a flowof air in the air tube 44 which then produces a low velocity fluifingair jet issuing from the upper nozzle end of the air tube concurrentlywith the air flow through the feed tube 27. As the strands offilamentary material are picked up by the pickup nozzle 26 or 26a of thefeed tube 27 or 27a, they are transported therethrough by the air flowin the feed tube and are projected at high speed out the open deliveryend 41 of the feed tube and straight upward through the convergingpassageway 43 and mouth opening 42 of the filling head and through theneck 39 of the bulb into the interior of the latter. Simultaneously withthe introduction of the filamentary material into the bulb, the fiufiingair jet emanating from the air nozzle 45 concurrently with theintroduction of the filamentary material into the bulb acts to swirl thestrands of filamentary material about the interior of the bulb (in thegeneral path denoted by the dotted line arrows in Fig. 2) as soon asthey enter the bulb proper and distribute them uniformly throughout theinterior of the bulb. The end result, therefore, is to dispose the totalnumber of strands of shredded foil or other filamentary materialconstituting the prescribed charge or loading for the bulb 38, in

the form of a loosely arranged mass of indiscriminately crumpled andintertwined strands distributed more or less uniformly throughout theinterior space of the bulb proper, as shown at 51 in Fig. 3. Theparticular flash lamp 52 illustrated in Fig. 3 is of the miniature typerecently introduced on the market and disclosed and claimed inco-pending application Serial No. 421,510, Anderson et al., filed April7, i954, and assigned to the assignee of the present invention. Theflash lamp' 52 includes, in addition to the bulb 38 and the charge 51 offilamentary material in the bulb, a mount 53 butt-sealed into the bulband a base 54 suitably secured to the neck end of the bulb, as byconventional basing cement. The mount 53 comprises a pair of leading-inwires 55 sealed through the neck end 39 of the bulb and connected attheir outer ends to the end or eyelet contact 56 and side or shellcontact 57, respectively, of the lamp base 54. Interiorly of the bulb,the leading-in wires 55 extend in more or less parallel relation to apoint in the vicinity of the central region of the bulb where they arebridged by an ignition filament 58 preferably in the form of a shortlength of fine tungsten wire having a wire diameter of the order of 1mil or less. The inner end of the leadingin wires 55 are provided withsmall coatings or beads 59 of a suitable primer or fulminating materialwhich partially embed the ends of the ignition filament 58 and, inconjunction therewith, form the ignition means for the flash lamp. Thebulb 38 also contains a combustionsupporting gas, such as oxygen, at asuitable pressure which, in the case of the particular lamp illustrated,amounts to around 700 millimeters of mercury.

In the modification shown in Fig. 7, the fiuffing air jet, in place ofbeing provided by a separate air tube 44 disposed within the fillinghead 1 or In and open to the atmosphere as in Figs. 1 and 2, is providedinstead by a small passageway 60 extending through the wall of thefilling head near the upper end thereof. As shown, the

and the inner end portion of the said passageway 60 extends at an angleof at least 15 to the vertical (i. e., to the axis of the funnel-shapedfoil-injection passageway 43 in the filling head) whereby to direct theair jet emerging from the nozzle end of the passageway 60 at acorresponding angle into the bulb 38 seated in loading posi tion on thefilling head. The outer end of the passageway 60 is open to theatmosphere to thereby permit air from the atmosphere to be bled or drawninto the passageway to form the flufiing air jet at the inner or nozzleend thereof when a bulb 38 is seated in loading position on the fillinghead and the latter is connected to the vacuum line. The air passageway60 may conveniently be formed by a drilled hole in the wall of thefilling head, and the diameter of the hole should be within the limitsspecified hereinbefore for the inside diameter of the air tube 44 in theform of the invention shown in Figs. 1, 2 and 4.

Since the lip of the mouth opening 42 of the foilinjection passageway 43in the filling head is normally spaced from or located below the lowerend or rim of the neck portion 39 of a bulb 38 seated in loadingposition on the filling head, the nozzle end of the air passage way 60in the modified form of the invention shown in Fig. 7 is thereforelocated wholly outside the bulb. As a result, the air jet emanating fromthe upper or nozzle end of the air passageway 60 passes angularlyacross, as well asin'to, the neck opening of the bulb so that itactually intersects the path of travel of the filamentary material intothe bulb during the loading operation. This, however,

' does not hamper or interfere with the passage of the filamentarymaterial into the bulb to any objectionable extent.

Instead of terminating the upper or nozzle end of the air passageway 60in Fig. 7 at the lip of the mouth open ing 42 in the filling head, thesaid passageway 60 may be extended, as shown in Fig.- 8, by theinsertion of a short tube 'or'nozzle extension 61 into the upper end ofthe passageway, so as to locate the nozzle opening entirely within thebulb 38 in a position corresponding to that of the nozzle opening of theair tube 44 in Figs. 1 and 2.

Also, in place of bleeding or drawing air from the surroundingatmosphere into the air tube 44 or the air passageway 60 to form thefluffing air jet, the air for the fluffing air jet may be suppliedinstead from a low pressure compressed air source, as shown in Fig. 8.For such purpose, the outer end of the air tube 44 or the air passageway60 of the respective filling head 1 or 1a may be connected to thecompressed air source by a connecting air line or pipe 62 or 62acontaining an electrically actuated control valve 63 or 63a. The valve63 or 63a is opened, .to produce a low velocity air jet from the nozzleend of the air tube 44 or air passageway 60, concurrently with theconnection of the filling head 1 to the vacuum line by the opening ofthe valve 34 or 34a, or in other words concurrently with the loading ofthe bulb with filamentary material. For this purpose, .the operation ofthe valve 63 or 63a in the compressed air line 62 or 62:: may

be controlled by the same switch 35 which controls the connection of thefilling head 1 or 10 to the vacuum line. To this end, the energizingcoils of the valves 34 and 63, which respectively control the connectionof fill ing head 1 to the vacuum line and the supply of compressed airto the respective flufiing air jet nozzle, are connected in parallelbranch circuits 64 and 65, respectively, of an operating circuit 66(Fig. 9) which is energized when the switch 35 is in one of its twoalternative closed positions .as determined by the engagement of the cam37 with the control arm 67 of the switch 35. Likewise, the energizingcoils of the valves 34a and 63a, which respectively control theconnection of filling head 1a to the vacuum line and the supply ofcompressed air to the respective fluffingair jet nozzle, are connectedin parallel branchcircuits 68 and 69 of an alternate operating circuit70 which is energized when the switch 35 is in the other one of its twoalternative positions.

Although a preferred embodiment of our invention has been describedherein, it will be understood that the invention is not to be limited tothe specific construction and arrangement of parts shown, but that theymay be widely modified within the spirit and scope of our invention asdefined by the appended claims.

What we claim as new and desire to secure by Letters Patent of theUnited States is:

1. The method of feeding fine strands of material into and distributingthem within a container having an opening therein which comprisesentraining the material in a gaseous fluid, guiding the entrainedmaterial toward the opening in the container, bleeding off the fluid ata point near the opening in the container and in a direction sharplyaway from the interior of the container to cause the entrained materialby its inertia to enter the container through the opening, and directinga low velocity air jet into the container concurrently with theinjection of the said strands thereinto to thereby fluif out the strandsupon entry into the container.

2. The method of introducing fine strands of combustible material into aflash lamp bulb which comprises arranging the bulb with its openingopposite and in vacuum-tight communication with an open delivery end ofa passageway, presenting the strand-s of combustible material to theopen entrance end of such passageway, drawing vair through saidpassageway and laterally out therefrom at a location adjacent the bulbopening and remote from the inermost space of said bulb .to create asuction .in said passageway serving to carry the strands therethroughand project them into said bulb, and directing a low velocity air jetinto the bulb concurrently with the injection of the said combustiblematerial thereinto to thereby fluff out the strands of combustiblematerial upon entry into the bulb.

3. The method set forth in claim 2 wherein the said low velocity air jetis directed into the bulb at an angle of at least approximately 15 tothe axis of the bulb.

4. The method of introducing fine strands of combustible material into aflash lamp bulb which comprises positioning the open neck end of a bulband .an open delivery end of a feed conduit in vacuum-tightcommunication with each other within an enclosure and in opposedlongitudinally separated relation with the delivery end of the conduitlocated adjacent to and wholly outside the said bulb, presenting thestrands of combustible material .to the open entrance end of saidconduit, exhausting said enclosure at a point exteriorly of said bulb todraw the air in said feed conduit laterally out from its delivery endand through the separation space between the said delivery end and theopen neck end of the bulb whereby to create a suction in said conduitserving to carry the strands therethrough and project them into thebulb, and directing a low velocity air jet into the bulb concurrentlywith the projection of the said strands thereinto to .thereby fluff outthe strands upon entry into the bulb.

5. The method of introducing fine strands of combustible material into aflash lamp bulb to develop the combustible element therein whichcomprises presenting the strands to the entrance end of a conduitleading into one end of and terminating within a chamber open at itsother end, seating the bulb vacuum-tight against the open end of thechamber with its open neck end opposite and longitudinally separatedfrom the terminal end of said conduit so that the said terminal end ofthe conduit is located wholly outside the bulb, exhausting the chamberat a point exteriorly of the bulb to withdraw the air from said bulb andsaid conduit through the separation space between the end of the bulbneck and the terminal end of the conduit whereby to create a suction insaid conduit serving to draw the strands therethrough and project themfrom its terminal end into the said bulb, and directing a low velocityair jet angularly into the bulb concurrently with the projection of thesaid strands thereinto to thereby flutf out the strands upon entry intothe bulb.

6. Aparatus for introducing fine strands of filamentary material into acontainer having a single open neck end, comprising an open-ended feedconduit, seating means adjacent the open delivery end of and connectedvacuumtight to said feed conduit for seating the container invacuum-tight communication with the said end of the conduit, saidconduit end being disposed in a position relative to the said seatingmeans to locate the said conduit end in opposed relation to the openneck end of the container and outwardly removed from the inner end ofthe container neck, means connecting said conduit with a source ofvacuum to define an exhaust path leading sharply away from the interiorof the conduit at a point adjacent its delivery end to thereby draw airthrough and create a suction in said conduit from its entrance endserving to carry the strands therethrough and project them into saidcontainer, and air jet means located adjacent the delivery end of saidconduit to direct a low velocity air jet into the container concurrentlywith the introduction of the filamentary material thereinto.

7. Apparatus of the character set forth in claim 6 wherein said air jetmeans comprises an inner nozzle end directed into the bulb and an outerend open to the atmosphere.

8. Apparatus for introducing fine strands of filamentary material into acontainer having a single opening comprising a loading head having achamber, a feed tube extending into and terminating within said chamberand having an open inner end, container-seating means on said loadinghead for connecting the opening of said container in vacuum-tightcommunication with the open inner end of said feed tube, said tube endbeing disposed in a position relative to the said seating means tolocate the said tube end opposite and spaced endwise from the containeropening so as to be located wholly outside the container, meansconnecting said chamber to a source of vacuum to exhaust the chamber andwithdraw the air in said tube out the said inner end thereof and sharplyaway from said tube end to thereby create a suction in said tube servingto carry the strands therethrough and project them into the container,said loading head being provided with air jet means for directing a lowvelocity air jet into the container concurrently with the projection ofthe filamentary material thereinto.

9. Apparatus .for introducing fine strands of combustible material intoa flash lamp bulb having a single open neck end, comprising a loadinghead having a chamber provided with an opening thereinto and having anannular seat around said opening against which the bulb is adapted toseat to connect the open neck and of the bulb in vacuum-tightcommunication with the said chamber, a feed conduit extending into thesaid chamber and having an open inner end directed toward and alignedwith the said opening in the chamber, said conduit end being disposed ina position relative to the said seat to locate the said conduit endopposite and spaced endwise from the bulb neck opening so as to belocated wholly outside the bulb, means connecting said chamber to asource of vacuum to exhaust the chamber and withdraw the air in saidconduit out the said inner end thereof and sharply away from said tubeend to thereby produce a suction in said conduit serving to carry thestrands therethrough and project them into the bulb, said loading headbeing provided with air jet means for directing a low velocity air jetinto the container con-currently with the projection of the filamentarymaterial thereinto.

10. Apparatus of the character set forth in claim 9 wherein said air jetmeans comprises an inner nozzle end directed into the bulb and an outerend open to the atmosphere.

11. Apparatus of the character set forth in claim 9 wherein the said airjet means directs the air jet there from into the bulb at an angle of atleast 15 to the axis of the bulb.

12. Apparatus of the character set forth in claim 9 wherein the said airjet means comprises an air passageway having a cross-sectional arearanging between A to the cross-sectional area of the neck opening ofsaid bulb.

13. Apparatus for introducing fine strands of combustible material intoa flash lamp bulb having a single opencnded cylindrical neck portion,said apparatus comprising a hollow filling head having a circular mouthopening at one end of a diameter at most approximately equal to theinside diameter of the bulb neck, the inner wall of said hollow fillinghead converging toward said mouth opening to form a funnel-shapedpassageway leading thereto, said container having an external annularseat around its said open end against which the bulb is adapted to seatapproximately vacuum-tight with its open neck end located outwardly ofand directed toward and aligned with the said mouth opening, a feed tubeextending into the other end of and straight through the hollow interiorof the loading head in alignment with and terminating short of the mouthopening thereof and having its inner end open, exhaust means connectedto said filling head at a location behind the inner end of said feedtube for withdrawing the air from the filling head and the bulb andcreating a suction of air in the feed tube to cause the strands to besucked through the said tube and projectod from its inner end throughthe said mouth opening and into the bulb, and air jet means in saidfilling head having a nozzle end located adjacent and directed outwardiyof the said mouth opening at an angle of at least to the axis thereoffor directing a low velocity air jet into the bulb concurrently with theprojection of the combustible material thereinto.

l4. Apparatus of the character set forth in claim 13 wherein said airjet means comprises an inner nozzle end, and an outer end open to theatmosphere.

15. Apparatus of the character set forth in claim 13 wherein the saidair jet means comprises an air passageway having a cross-sectional arearanging between to 5,; the cross-sectional area of the neck opening ofthe bulb and having an :air inlet end open to the atmosphere.

16. Apparatus of the character set forth in claim 13 wherein the saidair jet means comprises an air tube extending through the interior ofsaid filling head and through the mouth opening thereof and having itsair 12 inlet end open to the atmosphere, said air tube being firmlyanchored in place to the inner end of said feed tube.

17. Apparatus for introducingfine strands of combustible material into aflash lamp bulb having a single openended cylindrical neck portion, saidapparatus comprising a hollow loading head having a circular mouthopening at one end of a diameter at most approximately equal to theinside diameter of the bulb neck, the inner wall of said hollow fillinghea-d converging toward said mouth opening to form a funnel-shapedpassageway leading thereto, said filling head having an external annularseat around its said open end against which the bulb is adapted to seatapproximately vacuum-tight with its open neck end located outwardly ofand directed toward and aligned with the said mouth opening, a feed tubeextending into the other end of and straight through the hollow interiorof the loading head in alignment with but terminating short of the mouthopening thereof and having its inner end open, exhaust means including avacuum line connected to said filling head at a location behind theinner end of said feed tube for withdrawing the air from said fillinghead and bulb and creating a suction of air in the feed tube to causethe strands to be sucked through the said tube and projected from itsinner end through the said mouth opening and into the bulb, anelectrically operated control valve in said vacuum line, air jet meansin said filling head having a nozzle end located adjacent and directedoutwardly of the said mouth opening at an angle of at least 15 to theaxis thereof for directing a low velocity air jet into the bulbconcurrently with the projection of the combustible material thereinto,said air jet means being connected at its other end to a low pressurecompressed air line, an electrically operated control valve in saidcompressed air line, and switch means in the electrical operatingcircuit for each of said valves for con trolling the operation thereofto effect the simultaneous opening of the valves so as to concurrentlyconnect the filling head to the vacuum line and the air jet means to thecompressed air line.

References Cited in the file of this patent UNITED STATES PATENTS2,115,423 Korver Apr. 26, 1938 2,347,046 Geiger Apr. 18, 1944 2,359,029Goldberg Sept. 26, 1944

